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在 VB 编程中经常需要和文件系统打交道，比如获取硬盘的剩余空间、判断文件夹或文件是否存在等。在VB 推出文件系统对象(File System Object)以前，完成这些功能需要调用 Windows API 函数或者使用一些比较复杂的过程来实现，使编程复杂、可靠性差又容易出错。使用 Windows 提供的的文件系统对象，一切变得简单多了。以下笔者举出一些编程中比较常用的例子，以函数或过程的形式提供给大家，读者可在编程中直接使用，也可以改进后实现更为强大的功能。 要应用 FSO 对象，须要引用一个名为 Scripting 的类型库，方法是，执行 VB6.0 的菜单项“工程/引用”，添加引用列表框中的“Microsoft Scripting Runtime”一项。然后我们在“对象浏览器”中就可以看到 Scripting 类型库下的众多对象及其方法、属性。 1、判断光驱的盘符： Function GetCDROM() ' 返回光驱的盘符(字母) Dim Fso As New FileSystemObject '创建 FSO 对象的一个实例 Dim FsoDrive As Drive, FsoDrives As Drives '定义驱动器、驱动器集合对象 Set FsoDrives = Fso.Drives For Each FsoDrive In FsoDrives '遍历所有可用的驱动器 If FsoDrive.DriveType = CDRom Then '如果驱动器的类型为 CDrom GetCDROM = FsoDrive.DriveLetter '输出其盘符 Else GetCDROM = "" End If Next Set Fso = Nothing Set FsoDrive = Nothing Set FsoDrives = Nothing End Function 2、判断文件、文件夹是否存在： '返回布尔值:True 存在，False 不存在，filername 文件名 Function FileExist(filename As String) Dim Fso As New FileSystemObject If Fso.FileExists(filename) = True Then FileExist = True Else FileExist = False End If Set Fso = Nothing End Function '返回布尔值:True 存在，False 不存在，foldername 文件夹 Function FolderExist(foldername As String) Dim Fso As New FileSystemObject If Fso.FolderExists(foldername) = True Then FolderExist = True Else FolderExist = False End If Set Fso = Nothing End Function 3、获取驱动器参数: '返回磁盘总空间大小(单位：M)，Drive = 盘符 A ,C, D ... Function AllSpace(Drive As String) Dim Fso As New FileSystemObject, Drv As Drive Set Drv = Fso.GetDrive(Drive) '得到 Drv 对象的实例 If Drv.IsReady Then '如果该驱动器存在(软驱或光驱里有盘片，硬盘存取正常) AllSpace = Format(Drv.TotalSize / (2 ^ 20), "0.00") '将字节转换为兆 Else AllSpace = 0 End If Set Fso = Nothing Set Drv = Nothing End Function '返回磁盘可用空间大小(单位：M)，Drive = 盘符 A ,C, D ... Function FreeSpace(drive) Dim Fso As New FileSystemObject, drv As drive Set drv = Fso.GetDrive(drive) If drv.IsReady Then FreeSpace = Format(drv.FreeSpace / (2 ^ 20), "0.00") End If Set Fso = Nothing Set Drv = Nothing End Function '获取驱动器文件系统类型，Drive = 盘符 A ,C, D ... Function FsType(Drive As String) Dim Fso As New FileSystemObject, Drv As Drive Set Drv = Fso.GetDrive(Drive) If Drv.IsReady Then FsType = Drv.FileSystem Else FsType = "" End If Set Fso = Nothing Set Drv = Nothing End Function 4，获取系统文件夹路径： '返回 Windows 文件夹路径 Function GetWindir() Dim Fso As New FileSystemObject GetWindir = Fso.GetSpecialFolder(WindowsFolder) Set Fso = Nothing End Function '返回 Windows\System 文件夹路径 Function GetWinSysdir() Dim Fso As New FileSystemObject GetWinSysdir = Fso.GetSpecialFolder(SystemFolder) Set Fso = Nothing End Function 5，综合运用：一个文件备份通用过程： 'Filename = 文件名，Drive = 驱动器，Folder = 文件夹(一层) Sub BackupFile(Filename As String, Drive As String, Folder As String) Dim Fso As New FileSystemObject '创建 FSO 对象实例 Dim Dest_path As String, Counter As Long Counter = 0 Do While Counter < 6 '如果驱动器没准备好，继续检测。共检测 6 秒 Counter = Counter + 1 Call Waitfor(1) '间隔 1 秒 If Fso.Drives(Drive).IsReady = True Then Exit Do End If Loop If Fso.Drives(Drive).IsReady = False Then '6 秒后目标盘仍未准备就绪，退出 MsgBox " 目标驱动器 " & Drive & " 没有准备好！ ", vbCritical Exit Sub End If If Fso.GetDrive(Drive).FreeSpace < Fso.GetFile(Filename).Size Then MsgBox "目标驱动器空间太小！", vbCritical '目标驱动器空间不够，退出 Exit Sub End If If Right(Drive, 1) <> ":" Then Drive = Drive & ":" End If If Left(Folder, 1) <> "\" Then Folder = "\" & Folder End If If Right(Folder, 1) <> "\" Then Folder = Folder & "\" End If Dest_path = Drive & Folder If Not Fso.FolderExists(Dest_path) Then '如果目标文件夹不存在，创建之 Fso.CreateFolder Dest_path End If Fso.CopyFile Filename, Dest_path & Fso.GetFileName(Filename), True '拷贝，直接覆盖同名文件 MsgBox " 文件备份完毕。", vbOKOnly Set Fso = Nothing End Sub Private Sub Waitfor(Delay As Single) '延时过程，Delay 单位约为 1 秒 Dim StartTime As Single StartTime = Timer Do Until (Timer - StartTime) > Delay Loop End Sub 作者信息： 张庆 Email:zhangking at 263.net QQ: 9365822
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